I sell all of the above and what you feel comfortable shooting is the most important thing in hunting ducks, geese or anything else. If the gun is going to kick your butt everytime you shoot it, you are not gonna shoot so good. I can have about what I want from my store, but I still prefer the 2 3/4" Browning A-5 in Improved Cylinder whether shooting ducks or geese. I shot Bismuth and I have no problem at all. I feel confident in my gun and that makes all the difference in the world. The bigger shells are for to increase sales mainly. A fellow told me at the SHOT show several years ago that the average hunter back East needed a 4 power scope and out West a 6 power. He said a 40 MM was sufficient and I agree with him. You can usually use the binos or spotting scopes for the glassing and use the scope for shooting. But the scopes were made in higher powers and diameters to satisfy the public and I think to a certain degree the 3 1/2" guns were developed to satisfy the need for more power, which I really don't think you have if you will look at the 2 3/4" FPS and the 3" and the 3 1/2" FPS. If the shot is done correctly and placed where it should be then the kill will be effected, but I really think the larger or longer lengths contribute to many birds being crippled and lost due to hunters thinking they can take longer shots. My two cents worrth but you should remember...................take a kid hunting or fishing.......................